Long-Tailed Weasel

A small yet powerful predator.

October 14, 2013

For the long-tailed weasel (Mustela frenata), weight control isn't a matter of vanity–it's imperative for survival. In addition to aboveground hunting, this lithe relative of wolverine, badger, and skunk makes use of its slender physique in pursuing prey such as mice, voles, and chipmunks through their underground burrows. While it consumes the equivalent of 20 to 40 percent of its body weight daily, it knows when it's eaten enough. If faced with an overabundance of food, the weasel will cache the excess in its own nest rather than eating enough to hamper its next hunt.

The weasel's taste for birds and eggs makes it a hazard in the henhouse, but for gardeners, taking a live-and-let-live approach can pay off; according to a 1951 study, a population of 8,000 long-tailed weasels in one Colorado county dispatched more than 10 million rodents annually.


With a range that extends from southern Canada to northern Peru, the long-tailed weasel–so named for the black-tipped appendage held at a 45-degree angle as its owner bounds along–comprises 42 subspecies that thrive in alpine, woodland, aspen parklands, and even tropical zones. While the northerners don bright white coats in winter to facilitate hunting and evade predation in the snow, denizens of southern climes maintain their cinnamon brown coats year-round.

The elusive weasel has a home range of up to 40 acres in summer and more than 400 in winter. It can be difficult to distinguish from its cousin the ermine, which also sports a black-tipped tail, wears white in winter, and favors eggs when the opportunity arises.